Electrical switch



Oct. 24, 1950 BOWIE 2,526,845

ELECTRICAL SWITCH Filed July 51, 1947 2 Sheets-Sheet 1 IN V EN TOR.

Oct. 24, 1950 BOWIE 2,526,845

ELECTRICAL SWITCH Filed July 51, 1947 2 Sheets-Sheet 2 INVENTOR.

Patentecl Oct. 24, 1950 UNITED STATES PATENT OFFICE ELECTRICAL SWITCH Augustus Jesse Bowie, San Francisco, Calif.

Application July 31, 1947, Serial No. 765,081

8 Claims. 1

It is the object of this invention to engage the movable elements of switch contacts, such as tion of the engaging surfaces when pressure is being applied. In my invention, after full contact engagement, there is no substantial contact motion during the application of high pressure. This is accomplished by moving the clip after contact engagement, 2. short distance to apply high pressure, and then allowing substantial further motion thereof without appreciable pressure change, and thus allow for the inevitable variation in the action of the different poles of the switch.

In every gang operated switch it is impossible to obtain exact contact positions of the different poles, and substantial variations must be allowed for the different poles. This is in order to take care of the distortion, warping, and lost motion of the various switch parts. i

After full contact engagement further blade motion carries the clip so that relativemotion of the contacts is negligible, and is taken up by the play of the carriage on which the clip mounts, and

the freedom of the guides on which it moves. This is accomplished generally by moving the clip car-'- riage at right angles to the blade end.

) Fig. l is a side elevation of one pole of a gang switch, and Fig. 2 is a plan thereof.

Fig. 3 is an end elevation of the clip assembly, and Fig. 4 is a plan thereof. Fig. 5 isa side elevation thereof. g I 1 Fig. 6 is an end view of the clip face and roller, and Fig. '7 is a plan thereof.

1 is a clip cap; 2, 2 are clip faces or may be termed contact shoes; 3 is a blade end; 4 is a spring clipin which faces 2, 2 mount. 5 is a clip shunt, and 6 is an outgoing lead from the clip. 1 is a, clip support base; 8, 8 are support springs for base l, The contact shoes2, 2 are mounted on the movable base 1, but have a slight movement in the plane of the blade suflicient to cause the rollers l l, 'l l to operate. 9, '9 are pressure way supports with ways 9A, 9A. H, II, are pressure rollers mounted on shafts l4, [4, in slotted supports l0, I0. l3, iii are guide rods for base I; I2 is a bumper on which blade end 3 impinges to force base 1 down. Ways 9A, 9A terminate the up travel of base I insuring ample pressure from springs at the top end of the stroke.

V 'struction high pressure on clips has been obtained I6 is a clip insulator, and I! is a rotating insulator. I8 is a hinge insulator. See Figs. 1 and 2.

I9 is a blade mounted on pin 25), in hinge cap 2| to which bridge 22 is secured. This provides a support for bearing 25 in which shaft 25 fastened to insulator top 23 rotates. Top crank 26 mounts on shaft 24, and has a crank pin 21 secured therein. Connecting rod 28 with the universal joints 30, and 3| operates the blade thru pin 29. Base crank 32 attached to rotating insulator fl operates the blade by moving thru This crank has a pin 33, connected to control rod 34 for operating single pole or gang switches.

In closing the switch, blade end 3 enters clip faces 2, 2 and bottoms on bumper i2, springs 8, 8 holding the clip support 1 in the top position against ways 9A, 9A. Further motion depresses rollers H, H from free side position into engagement with ways 9A, 9A which are so positioned that when the rollers come into full bearing they puta high pressure on the clip faces. The travel of these rollers on the ways allow for variations in blade and clip positions without changes in pressure. It is essential to hold the clip from motion until the blade has entered it to make full contact therewith. While springs 8, 8 perform this function other methods may be be used to prevent clip motion until blade and clip contacts are fully established. In past conby the use of .a pair of inclined toggles on each clip face which are brought into toggle by a blade motion depressing the clip faces to an exact position. Owing to the various yields of gang switch parts, while this will give a high pressure from toggle action, it has been impossible to secure exact toggle positions in all phases. I overcome this difficulty by allowing a material overtravel without change of clip high pressure. This is ac! complished by the parallel faces 9A, 9A on which rollers II, II slide, giving a constant pressure at any position of overtravel. The rollers which before clip motion starts downward, are in depressions in 9A, 9A must leave these depressions before engaging the ways, and this puts a desirable initial resistance to down carriage motion in addition to that of springs 8, 8, insuring full entrance of the blade in the clip before carriage motion. This is an improvement over any toggle action devised.

As the faces 9A, 9A, must have a close tolerance of spacing, this can be met by familiar adjustment methods, such as by bolts 36, 36 in bases 38, 38, pressing on the back of supports 9, 9 for the ways, and also by the use of shims 31, 31 be- In no past construction has it been possible to have material either clip and blade, or control motion after full contact without appreciable relative motion of the contact surfaces. It had been my endeavor to approximate this condition in past patents, wherein the blade was moved by a crank and connecting rod on dead center in closed posi tion, and when nearing this position. f the crank,

least motion of the contacts while applying:

the high pressure. This motion is not made when the blade and clip move together in a line normal 7 to the blade end. These facts are capable of definite mathematical proof, and the freedom from motion under high pressure has not been attained heretofore by any construction.

While, as I show, rollers operating on the ways are desirable, sliding engaging surfaces may be used instead of rollers.

The pressure of clip 4 is so moderate that it will not cause abrasion of the contacts. High pressure is obtained b further motion thru bumper l2. This insures high pressure for the contacts without abrasion of faces 2, 2, or blade end 3. With silver contacts this is particularly essential to avoid destruction of the contact surfaces with movement under high contact pressure.

Ways 9A, 9A are each provided with depressed surfaces, clearing the top rollers l l, l l at the start of the closing stroke under no pressure (see Fig. 3), but after a slight motion of the clip carriage 1 downward, the rollers engage the bossed parts of ways 9A. 9A subjecting the contacts to a high pressure of definite amount. As these bossed surfaces are parallel, there is no substantial pressure change over a considerable motion of carriage J.

Having described my invention what I claim is:

1. In an electrical switch, a pair of insulating supports, a pair of cooperating contacts, one of which is mounted on one of said insulating supports and is adapted to move to engage the second contact which is movably mounted on said second insulating support, said second contact comprising a pair of shoes, each of which is adapt ed to be pressed by a pair of substantially parallel ways mounted on one of said insulating supports, and by a pair of rollers or bosses engaging said ways and actuated by said movable contact after said contacts have been engaged, and adapted to apply high pressure to said contacts after'full contact engagement has been established, and means for preventing relative motion between said contacts during said high pressure'application.

2. In an electrical switch, a blade, contact shoes for contacting therewith, a yieldable carriage on which said shoes are mounted, means for operat-' ing said carriage after said blade and shoes have fully contacted, and means for then applying high pressure between said blade and shoes without relative motion of said contacts, said carriage operation comprising an initial motion during which high pressure is applied, and an over travel follow without materially affecting said high pressure. 7

In an electrical switch, a blade, contact shoes for contacting therewith, a yieldable carria e on which said shoes are mounted, means for operating said carriage after said blade and shoes have fully contacted, and means for then applying high pressure between said blade and shoes without relative motion of said contacts, a pair of rollers engaging a pair of parallel ways for applying high pressure to said contacts, each way being adapted to exert pressure on each shoe.

'4. In an electrical switch, a blade, contact shoes for contacting therewith, yieldable carriage on which said shoes are mounted, means for operating said carriage after said blade and shoes have fully contacted, and means for then applying high pressure between said blade and shoes without relative motion of said contacts, and spring means acting on said carriage to prevent motion thereof until said blade and shoes are full engaged.

- 5. In an electrical switch, a blade, contact shoes for contacting therewith, a yieldable carriage on which said shoes are mounted, means for operating said carriage after said blade and shoes have fully contacted, and means for then applying high pressure between said blade and shoes without relative motion of said contacts, a pair of rollers engaging a pair of parallel ways for applying high pressure to said contacts, each way being adapted to exert pressure on each shoe, said rollers being free from said ways until said carriage moves to apply high pressure.

6. In an electrical switch, a blade, contact shoes for contacting therewith, a yieldable carriage on which said shoes are mounted, means for operating said carriage after said blade and shoes have fully contacted, and means for then applying high pressure between said blade and shoes without relative motion of said contacts, said shoes being provided with rollers for applying high pressure and with ways for engaging said rollers, said Ways being substantially parallel and providing a substantially fixed high pressure independent of carriage over travel.

'7. In an electric switch a pair of relatively movable contacts, means for engaging said contacts,means for applying high pressure between said contacts after engagement, and means for continuedfurther motion of said contacts with out relative motion of the contacting surfaces thereof.

8. In an electric switch a pair of relatively movable contacts, means for engaging said contacts, means for applying high pressure between said contacts after engagement, and means for continued further motion of said contacts without relative motion of the contacting surfaces thereof without appreciably altering said high pressure.

AUGUSTUS JESSE BOWIE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

